Snowmobile

ABSTRACT

A snowmobile has a frame, a ski connected to the frame, a seat connected to the frame for accommodating a driver of the snowmobile, a rear suspension assembly operatively connected to the frame, an endless track supported by the rear suspension assembly, a motor supported by the frame, and a continuously variable transmission (CVT) operatively connecting the motor to the endless track. The rear suspension assembly has a suspension assembly drive axle defining a drive axle rotation axis, and a drive sprocket mounted to the drive axle. The motor has a shaft rotatable about a shaft rotation axis. The drive axle rotation axis is positioned forwardly of the shaft rotation axis. The seat is positioned above the motor.

CROSS-REFERENCE

The present application is a continuation of U.S. patent applicationSer. No. 16/404,831, filed on May 7, 2019, which is a continuation ofU.S. patent application Ser. No. 16/029,278, filed on Jul. 6, 2018,which claims priority to U.S. Provisional Patent Application No.62/529,244, filed on Jul. 6, 2017, the entirety of each of which isincorporated herein by reference.

TECHNICAL FIELD

The present invention relates generally to a snowmobile, and inparticular to a configuration of its motor and transmission.

BACKGROUND

Snowmobiles are designed for travel over snow on a variety of terrains.However, due to its size, a snowmobile may be restricted from navigatingareas where obstacles (e.g., vegetation) are dense. Notably, thesnowmobile typically includes two laterally-spaced skis which impart asignificant width to the snowmobile such that maneuvering betweenobstacles may be difficult. In order to address this, in somesnowmobiles, the skis can be adjusted to be positioned closer to oneanother. Nevertheless, certain components of the snowmobile's powertrainmay still impose a significant width to the snowmobile.

In some cases, a motorcycle may be adapted to travel over snow byreplacing its front and rear wheels by a ski and a tracked suspensionassembly respectively, thus resulting in a relatively narrow vehiclecapable of travelling over snow. However, motorcycles are generally notoptimized for winter use and may thus exhibit poor performance whenmodified as described. For example, due to the configuration of themotorcycle's powertrain (including, for example, its engine andtransmission), the weight distributed on the ski and the trackedsuspension assembly may not be optimal for travelling over snow.Furthermore, certain components, such as the motorcycle's transmission,may not be suited for interaction with snow.

For these and other reasons, there is a desire for modification toexisting snowmobile designs.

SUMMARY

It is an object of the present invention to ameliorate at least some ofthe inconveniences described above.

In accordance with an aspect of the present technology, there isprovided a snowmobile. The snowmobile includes: a frame; a ski connectedto the frame; a seat connected to the frame for accommodating a driverof the snowmobile; a rear suspension assembly operatively connected tothe frame; an endless track supported by the rear suspension assembly; amotor supported by the frame; and a continuously variable transmission(CVT) operatively connecting the motor to the endless track for drivingthe endless track. The rear suspension assembly includes: at least oneslide rail; a suspension assembly drive axle defining a drive axlerotation axis; a drive sprocket mounted to the drive axle; and aplurality of idler wheels connected to the at least one slide rail. Thedrive sprocket of the rear suspension assembly is rotatable about thedrive axle rotation axis to drive the endless track. The motor includesa shaft rotatable about a shaft rotation axis. The drive axle rotationaxis is positioned forwardly of the shaft rotation axis of the shaft ofthe motor. The seat is positioned above the motor.

In some implementations, the CVT includes a primary pulley operativelyconnected to and driven by the motor, a secondary pulley operativelyconnected to and driven by the primary pulley, and a transmission beltconnecting the primary pulley to the secondary pulley. The primarypulley is rotatable about a primary pulley rotation axis, the primarypulley rotation axis extending parallel to the shaft rotation axis ofthe shaft of the motor, the primary pulley being operatively connectedto the shaft of the motor by one of a chain and a belt. The secondarypulley is rotatable about a secondary pulley rotation axis. Thesecondary pulley is operatively connected to the endless track to drivethe endless track.

In some implementations, the snowmobile also includes: a primary pulleyshaft defining the primary pulley rotation axis, the primary pulleybeing mounted to the primary pulley shaft to rotate therewith; and asecondary pulley shaft defining the secondary pulley rotation axis, thesecondary pulley being mounted to the secondary pulley shaft to rotatetherewith, the one of the chain and the belt being operatively connectedbetween the primary pulley shaft and the shaft of the motor.

In some implementations, the primary and secondary pulley shafts arerotatably supported by the frame.

In some implementations, the primary pulley rotation axis extendslaterally; and the primary pulley rotation axis is positioned forwardlyof the shaft rotation axis of the shaft of the motor.

In some implementations, the secondary pulley rotation axis ispositioned forwardly of the primary pulley rotation axis.

In some implementations, the secondary pulley is operatively connectedto the drive sprocket of the rear suspension assembly by a link; and theprimary and secondary pulleys of the CVT are disposed laterally betweenthe link operatively connecting the secondary pulley to the drivesprocket and the one of the chain and the belt operatively connectingthe primary pulley to the shaft of the motor.

In some implementations, the drive axle rotation axis is positionedrearwardly of the secondary pulley rotation axis.

In some implementations, the drive axle rotation axis is positionedrearwardly of the primary pulley rotation axis.

In some implementations, the secondary pulley rotation axis isvertically lower than the primary pulley rotation axis.

In some implementations, the ski is a single laterally centered ski.

In some implementations, the one of the chain and the belt is the chain.The snowmobile also includes: a first sprocket mounted to the shaft ofthe motor; and a second sprocket mounted to the primary pulley shaft.The chain is connected between the first and second sprockets tooperatively connect the shaft of the motor to the primary pulley.

In some implementations, the second sprocket has a smaller diameter thanthe primary pulley.

In some implementations, the motor is an internal combustion engine, theshaft of the motor is a crankshaft and the shaft rotation axis of theshaft of the motor is a crankshaft rotation axis.

According to another aspect of the present technology, there is provideda snowmobile. The snowmobile includes: a frame; a ski connected to theframe; a seat connected to the frame for accommodating a driver of thesnowmobile; a rear suspension assembly operatively connected to theframe; an endless track supported by the rear suspension assembly; amotor supported by the frame; and a continuously variable transmission(CVT) operatively connecting the motor to the endless track for drivingthe endless track. The rear suspension assembly includes: at least oneslide rail; a suspension assembly drive axle defining a drive axlerotation axis; a drive sprocket mounted to the drive axle; and aplurality of idler wheels connected to the at least one slide rail. Thedrive sprocket of the rear suspension assembly is rotatable about thedrive axle rotation axis to drive the endless track. The motor includesa shaft rotatable about a shaft rotation axis. The drive axle rotationaxis is positioned forwardly of the shaft rotation axis of the shaft ofthe motor. The seat is positioned above the shaft rotation axis of theshaft of the motor.

In some implementations, the CVT includes a primary pulley operativelyconnected to and driven by the motor, a secondary pulley operativelyconnected to and driven by the primary pulley, and a transmission beltconnecting the primary pulley to the secondary pulley. The primarypulley is rotatable about a primary pulley rotation axis, the primarypulley rotation axis extending parallel to the shaft rotation axis ofthe shaft of the motor, the primary pulley being operatively connectedto the shaft of the motor by one of a chain and a belt. The secondarypulley is rotatable about a secondary pulley rotation axis. Thesecondary pulley is operatively connected to the endless track to drivethe endless track.

According to another aspect of the present technology, there is provideda snowmobile. The snowmobile includes a frame; a ski connected to theframe; a seat connected to the frame for accommodating a driver of thesnowmobile; a rear suspension assembly operatively connected to theframe; an endless track supported by the rear suspension assembly; aninternal combustion engine supported by the frame; a continuouslyvariable transmission (CVT) operatively connecting the engine to theendless track for driving the endless track; and a fuel tank supportedby the frame and positioned rearwardly of the engine. The rearsuspension assembly includes: at least one slide rail; a suspensionassembly drive axle defining a drive axle rotation axis; a drivesprocket mounted to the drive axle; and a plurality of idler wheelsconnected to the at least one slide rail. The drive sprocket of the rearsuspension assembly is rotatable about the drive axle rotation axis todrive the endless track. The engine includes a crankshaft rotatableabout a crankshaft rotation axis. The drive axle rotation axis ispositioned forwardly of the crankshaft rotation axis.

In some implementations, the fuel tank is positioned rearwardly of theseat.

In some implementations, the CVT includes a primary pulley operativelyconnected to and driven by the motor, a secondary pulley operativelyconnected to and driven by the primary pulley, and a transmission beltconnecting the primary pulley to the secondary pulley. The primarypulley is rotatable about a primary pulley rotation axis, the primarypulley rotation axis extending parallel to the shaft rotation axis ofthe shaft of the motor, the primary pulley being operatively connectedto the shaft of the motor by one of a chain and a belt. The secondarypulley is rotatable about a secondary pulley rotation axis. Thesecondary pulley is operatively connected to the endless track to drivethe endless track.

In some implementations, the snowmobile also includes: a primary pulleyshaft defining the primary pulley rotation axis, the primary pulleybeing mounted to the primary pulley shaft to rotate therewith; and asecondary pulley shaft defining the secondary pulley rotation axis, thesecondary pulley being mounted to the secondary pulley shaft to rotatetherewith, the one of the chain and the belt being operatively connectedbetween the primary pulley shaft and the crankshaft.

For purposes of the present application, terms related to spatialorientation when referring to the snowmobile and components in relationto the snowmobile, such as “forward”, “rearward”, “left”, “right”,“above” and “below”, are as they would be understood by a driver of thesnowmobile sitting thereon in a normal riding position, with thesnowmobile in a straight ahead orientation (i.e. not steered left orright), and in an upright position (i.e. not tilted). When referring toa component alone, terms related to spatial orientation are describedwith respect to the component as disposed on the snowmobile.

Implementations of the present invention each have at least one of theabove-mentioned object and/or aspects, but do not necessarily have allof them. It should be understood that some aspects of the presentinvention that have resulted from attempting to attain theabove-mentioned object may not satisfy this object and/or may satisfyother objects not specifically recited herein.

Additional and/or alternative features, aspects, and advantages ofimplementations of the present invention will become apparent from thefollowing description, the accompanying drawings, and the appendedclaims.

BRIEF DESCRIPTION OF THE DRAWINGS

For a better understanding of the present invention, as well as otheraspects and further features thereof, reference is made to the followingdescription which is to be used in conjunction with the accompanyingdrawings, where:

FIG. 1 is a left side elevation view of a snowmobile;

FIG. 2 is a left side elevation view of the snowmobile of FIG. 1 withcertain components removed to expose part of a frame, an engine and acontinuous variable transmission of the snowmobile;

FIG. 3 is a top plan view of the snowmobile as shown in FIG. 2;

FIG. 4 is a front elevation view of the snowmobile as shown in FIG. 2;

FIG. 5 is a rear elevation view of the snowmobile as shown in FIG. 2;

FIGS. 6 and 7 are top and bottom plan views of a portion of thesnowmobile of FIG. 1 showing an exhaust system of the snowmobile;

FIG. 8 is a top plan view of the portion of the snowmobile shown inFIGS. 6 and 7 with an exhaust pipe of the exhaust system removed toexpose the continuous variable transmission of the snowmobile; and

FIG. 9 is a left side elevation view of the portion of the snowmobileshown in FIG. 6.

DETAILED DESCRIPTION

With reference to FIGS. 1 to 5, a snowmobile 10 includes a front end 12and a rear end 14 which are defined consistently with a forward traveldirection of the snowmobile 10. The snowmobile 10 includes a vehiclebody in the form of a frame 16 which includes a rear tunnel 18 and amotor module 20. The tunnel 18 is formed from sheet metal partsassembled to form an inverted U-shape when viewed from the front or rearend 12, 14. The inverted U-shaped tunnel 18 has a left side portion 18 aand a right side portion 18 b.

A motor 26, which in the present implementation is an internalcombustion engine (schematically illustrated in FIG. 1), is carried in amotor compartment defined in part by the motor module 20 of the frame16. The engine 26 provides propulsion of the snowmobile 10. The internalconstruction of the engine 26 may be of any known type such as atwo-stroke engine, a four-stroke engine or a diesel engine. It iscontemplated that the engine 26 could be replaced by other types ofmotors, such as, but not limited to, an electric motor or anelectric/internal combustion hybrid engine. In the presentimplementation, the engine 26 is a two-stroke, in-line, two cylinderinternal combustion engine. The engine 26 has a crankshaft 86 thatrotates about a crankshaft rotation axis 88 extending laterally (i.e.generally transversely to a longitudinal axis 15 of the snowmobile 10).As will be described in more detail further below, the crankshaft 86drives a drivetrain of the snowmobile 10 for propulsion of thesnowmobile 10 on the ground.

A fuel tank 28, supported on the tunnel 18, supplies fuel to the engine26 for its operation. The fuel tank 28 includes a cap 92 covering a fillopening of the fuel tank 28 and disposed behind a seat 60 of thesnowmobile 10.

The snowmobile 10 also comprises an exhaust system 90 for guidingexhaust gas away from the engine 26 to a surrounding environment of thesnowmobile 10. Notably, the exhaust system 90 comprises an exhaust pipe93 which is fluidly connected to the engine's exhaust ports 94, and amuffler 96 for reducing an amount of noise emitted by the exhaust system90. The exhaust pipe 93 is a tuned pipe in that it has a geometrysuitable for improving the efficiency of the engine 26.

An endless track 30 is positioned generally under the tunnel 18, and isoperatively connected to the engine 26 via a drivetrain including atransmission system 23. The endless track 30 has a front end 37 and arear end 39 opposite the front end 37. The endless track 30 is driven torun about a rear suspension assembly 32 connected to the frame 16 forpropulsion of the snowmobile 10. The endless track 30 has a plurality oflugs 31 extending from an outer surface thereof to provide traction tothe endless track 30.

The rear suspension assembly 32 includes a pair of drive sprockets 34mounted on a drive axle 35, multiple idler wheels 36 and a pair of sliderails 38 in sliding contact with the endless track 30. The drive axle 35on which the drive sprockets 34 are mounted defines a drive sprocketrotation axis 34 a which extends laterally (i.e., in a lateral directionof the snowmobile 10). The slide rails 38 are attached to the tunnel 18by a front suspension arm 40 and a rear suspension arm 50. The rearsuspension assembly 32 further includes a front shock absorber assembly42 and a rear shock absorber assembly 45, each of which includes a shockabsorber. It is contemplated that the snowmobile 10 could be providedwith a different implementation of the rear suspension assembly 32 thanthe one shown herein.

The seat 60 of the snowmobile 10 is a straddle seat which is connectedto the frame 16 and is adapted to accommodate a driver of the snowmobile10. In some implementations, the seat 60 may be configured toaccommodate a passenger. A footrest 64 is positioned on each side of thesnowmobile 10 below the seat 60 to accommodate the driver's feet. Eachof the left and right footrests 64 extends generally laterally outwardlyfrom corresponding left and right side portions of the frame 16.

The snowmobile 10 further comprises fairings 66 which enclose the engine26, the transmission system 23 and other components of the powerpacksuch as an air intake system. The fairings 66 can be removed to allowaccess to the engine 26 and/or the transmission system 23 and otherinternal components of the snowmobile 10 which may be required, forexample, for inspection or maintenance of the engine 26 and/or thepowerpack.

A ski 70 positioned at the forward end 12 of the snowmobile 10 isattached to the front suspension module 22 of the frame 16 through aspindle 72. The front suspension module 22 includes a fork 74 and ashock absorber 75. As shown in FIG. 3, the ski 70 is a single laterallycentered ski. In other words, the ski 70 is aligned with a centerline 73bisecting a width of the snowmobile 10. It is contemplated that, in someimplementations, the snowmobile 10 may comprise two skis (such as theski 70) which are positioned close to each other.

A steering assembly 80, including two front forks 82 and a handlebar 84,is provided generally forward of the seat 60. The front forks 82 arerotatably connected to the frame 16. A lower end of the front forks 82is connected to the front suspension module 22. The handlebar 84 isattached to an upper end of the front forks 82. The handlebar 84 ispositioned in front of the seat 60. The handlebar 84 is operativelyconnected to the ski 70 such that the handlebar 84 is used to rotate thefront forks, and thereby the ski 70, in order to steer the snowmobile10. A left handle 85 a and a right handle 85 b are disposed on left andright sides of the handlebar 84 respectively. A brake actuator (notshown), in the form of a hand brake lever, is provided on the lefthandle 85 a for braking the snowmobile 10 in a known manner A throttleoperator (not shown) in the form of a twist grip is mounted to the righthandle 85 b. Other types of throttle operators, such as afinger-actuated throttle lever and a thumb-actuated throttle lever, arealso contemplated.

In this implementation, the snowmobile 10 also comprises a heatexchanger system 130 for cooling the engine 26. The heat exchangersystem 130 comprises a radiator 132 and a fan 134. The radiator 132 isfluidly connected to the engine 26 such that coolant that is circulatedthrough the engine 26 is received at the radiator 132 where the coolantexchanges heat and is returned to the engine 26. The fan 134 isconfigured to blow air through the radiator 132 to aid in the convectiveheat exchange.

The snowmobile 10 includes other components such as a display cluster,an air intake system, and the like. As it is believed that thesecomponents would be readily recognized by one of ordinary skill in theart, further explanation and description of these components will not beprovided herein.

Turning now to FIGS. 6 to 8, the configuration of the transmissionsystem 23 and the engine 26 will now be described in more detail.

The transmission system 23 is a continuously variable transmission (CVT)and thus offers a continuous range of gear ratios. To that end, the CVT23 comprises a primary (drive) pulley 46 operatively connected to theengine 26, a secondary (driven) pulley 48 operatively connected to theendless track 30, and a transmission belt 52 which operatively connectsthe primary pulley 46 to the secondary pulley 48. More particularly, theprimary pulley 46 has a pair of opposed frustoconical belt drive sheaves102, 104 and the secondary pulley 48 has a pair of opposed frustoconicalbelt drive sheaves 106, 108. The transmission belt 52 is located betweenthe opposed pairs of drive sheaves 102, 104 and 106, 108.

A transmission ratio of the CVT 23 can be changed by moving the sheavesof one of the primary and secondary pulleys 46, 48 closer together andthe sheaves of the other of the primary and secondary pulleys 46, 48further apart. This causes the transmission belt 52 to ride higher onone pulley and lower on the other, thus affecting the transmission ratioof the CVT 23. In order to effect such a change in the transmissionratio of the CVT 23, the primary pulley 46 has centrifugal actuators 115connected to the drive sheave 104 which is moveable laterally (i.e., inan axial direction of the primary pulley 46) towards and away from thedrive sheave 102 which is laterally fixed. As is known, the centrifugalactuators 115 generally consist of centrifugal weights in the form ofadjusting arms. Each of the arms is connected to the movable sheave 104of the primary pulley 46 by a pin, and pivots outwards about itscorresponding pin. As they pivot, the arms are in contact withcorresponding rollers disposed on a spider fixed relative to the movablesheave 104. When the adjusting arms pivot outwards as a result ofcentrifugal force, they slide against their corresponding roller and theaxially movable sheave 104 is pushed towards the fixed sheave 102.

The primary pulley 46 has a primary pulley rotation axis 110 extendinglaterally and which is defined by a primary pulley shaft 112 onto whichthe primary pulley 46 is mounted. The primary pulley shaft 112 isrotatably supported by the frame 16 (e.g., via bearings). The primarypulley 46 is rotatable with the primary pulley shaft 112 such that thedrive sheaves 102, 104 rotate together with the primary pulley shaft112. The primary pulley 46 is operatively connected to the crankshaft 86of the engine 26. In particular, in this implementation, a sprocket 122is mounted on the primary pulley shaft 112 and another sprocket 124 ismounted on the crankshaft 86. A chain 125 operatively connects thesprocket 124 mounted on the crankshaft 86 to the sprocket 122 mounted onthe primary pulley shaft 112 such that the crankshaft 86 transmitstorque to the primary pulley 46 via the chain 125 and sprockets 122, 124and thus causes rotation of the primary pulley 46 about the primarypulley rotation axis 110. A chain case 113 covers the chain 125 andsprockets 122, 124. While in this implementation, a link interconnectingthe crankshaft 86 to the primary pulley shaft 112 is a chain, the linkmay be any other suitable type of link in other implementations. Forinstance, it is contemplated that, in other implementations, instead ofsprockets, pulleys are mounted on the crankshaft 86 and the primarypulley shaft 112 and a belt is looped about the pulleys such that thecrankshaft 86 transmits torque to the primary pulley 46 via the belt andpulleys. It is contemplated that, in yet other implementations, a gearis mounted on the crankshaft 86 and another gear is mounted on theprimary pulley shaft 112. The gear mounted on the crankshaft 86 drivesthe gear mounted on the primary pulley shaft 112 either directly, orthrough an intervening component, such as an idler gear.

As mentioned above, the transmission belt 52 operatively connects theprimary pulley 46 to the secondary pulley 48 to transmit torque thereto.In particular, as shown in FIG. 2, the transmission belt 52 is loopedaround both the primary pulley 46 and the secondary pulley 48. In thisimplementation, the transmission belt 52 is made of rubber, but it iscontemplated that it could be made of metal linkages or of a polymer.

The secondary pulley 48 has a secondary pulley rotation axis 114extending laterally and which is defined by a secondary pulley shaft 116onto which the secondary pulley 48 is mounted. The secondary pulleyshaft 116 is rotatably supported by the frame 16 (e.g., via bearings).The secondary pulley 48 is rotatable with the secondary pulley shaft 48such that the drive sheaves 106, 108 rotate together with the primarypulley shaft 112. The secondary pulley 48 is operatively connected tothe drive sprockets 34 of the rear suspension assembly 32 such that thesecondary pulley 48 transmits torque to the drive sprockets 34 which inturn drive the endless track 30. In this implementation, a sprocket 126is mounted on the secondary pulley shaft 116 and another sprocket 128 ismounted on the drive axle 35. A chain 127 operatively connects thesprocket 126 mounted on the secondary pulley shaft 116 to the sprocket128 mounted on the drive axle 35 such that the secondary pulley shaft116 transmits torque to the drive axle 35 via the chain 127 andsprockets 126, 128 and thus causes rotation of the drive sprockets 34about the drive sprocket rotation axis 34 a. A chain case 117 covers thechain 127 and sprockets 126, 128. While in this implementation, a linkinterconnecting the secondary pulley shaft 116 to the drive axle 35 is achain, the link may be any other suitable type of link in otherimplementations. For instance, it is contemplated that, in otherimplementations, instead of sprockets, pulleys are mounted on thesecondary pulley shaft 116 and the drive axle 35 and a belt is loopedabout the pulleys such that the secondary pulley shaft 116 transmitstorque to the drive axle 35 via the belt and pulleys. It is contemplatedthat, in yet other implementations, a gear is mounted on the secondarypulley shaft 116 and another gear is mounted on the drive axle 35. Thegear mounted on the secondary pulley shaft 116 drives the gear mountedon the drive axle 35 either directly, or through an interveningcomponent, such as an idler gear.

With reference to FIGS. 7 to 9, in this implementation, the sprockets122, 124 and the chain 125 are disposed on a right side of the CVT 23while the sprockets 126, 128 and the chain 127 are disposed on a leftside of the CVT 23. More specifically, the primary pulley 46, thesecondary pulley 48 and the transmission belt 52 are positionedlaterally between, on one lateral side thereof, the sprockets 122, 124and the chain 125 which operatively connect the engine 26 to the CVT 23,and on the other lateral side, the sprockets 126, 128 and the chain 127which operatively connect the CVT 23 to the drive axle 35. Inimplementations in which pulleys and a belt or other types of drivemembers (e.g., gears) operatively connect the engine 26 to the CVT 23and/or the CVT 23 to the drive axle 35, the primary pulley 46 and thesecondary pulley 48 are positioned laterally between the drive membersthat operatively connect the engine 26 to the CVT 23 and the drivemembers that operatively connect the CVT 23 to the drive axle 35.

As shown in FIGS. 8 and 9, the CVT 23 is positioned forwardly of theengine 26. In other words, a front end 118 of the engine 26 (i.e., afront surface 135 of a cylinder block and crankcase of the engine 26) isdisposed rearwardly of the CVT 23 including the primary pulley 46, thesecondary pulley 48 and the transmission belt 52. This positioning ofthe CVT 23 relative to the engine 26 may help minimize a combinedlateral extent of the engine 26 and the CVT 23 which, conventionally,are positioned side-by-side (i.e., laterally adjacent).

The primary and secondary pulleys 46, 48 of the CVT 23 are thereforepositioned between lateral sides 55, 57 of the engine 26. That is, theprimary and secondary pulleys 46, 48 are confined within a lateralextent of the engine 26. Furthermore, the rotation axes 110, 114 of theprimary and secondary pulleys 46, 48 of the CVT 23 are both locatedforwardly of the engine 26. In other words, the primary pulley rotationaxis 110 is positioned forwardly of the crankshaft rotation axis 88.Similarly, the secondary pulley rotation axis 114 is positionedforwardly of the crankshaft rotation axis 88. Moreover, the secondarypulley rotation axis 114 is positioned forwardly of the primary pulleyrotation axis 110. The secondary pulley rotation axis 114 is alsovertically lower than the primary pulley rotation axis 110.

For its part, the engine 26 is positioned further rearward than inconventional snowmobile designs. This distributes a greater proportionof weight of the snowmobile 10 and its driver onto the endless track 30rather than the ski 70 which may result in improved maneuvering of thesnowmobile 10 when travelling over deep snow.

For instance, in this implementation, the engine 26 is fully positionedabove (i.e. an entirety of the engine 26 is positioned above) theendless track 30 and rearward of the front end 37 of the endless track30. However, it is contemplated that, in some implementations, ratherthan the entirety, a majority of the engine 26 is positioned above theendless track 30 and rearward of the front end 37 of the endless track30, or that only part of the engine 26 is positioned above the endlesstrack 30 and rearward of the front end 37 of the endless track 30.Moreover, the drive sprocket rotation axis 34 a is positioned forwardlyof the crankshaft rotation axis 88. Furthermore, the seat 60 ispositioned above the engine 26. The engine 26 is positioned above thetunnel 18 of the frame 16.

Furthermore, the exhaust system 90 of the snowmobile 10 is positionedforwardly of the engine 26. More specifically, the exhaust pipe 93 hasan end 105 and an end 107. The end 105 of the exhaust pipe 93 is fluidlyconnected to exhaust ports 94 of the engine 26 via an exhaust manifold120 of the exhaust system 90. The end 105 is positioned rearwardly ofthe primary pulley rotation axis 110. The exhaust pipe 93 extendsforwardly from the end 105 of the exhaust pipe 93 past the secondarypulley rotation axis 114.

The muffler 96 is fluidly connected to the end 107 of the exhaust pipe93. The muffler 96 is positioned particularly low relative to the CVT23. Notably, in this implementation, part of the muffler 96 extendsbelow the secondary pulley rotation axis 114. Thus, as shown in FIG. 9,the exhaust pipe 93 extends forward from the end 105 of the exhaust pipe93 past the secondary pulley 48 and downward in front of the secondarypulley 48 where the end 107 of the exhaust pipe 93 is connected to themuffler 96. The muffler 96 then extends rearward under the secondarypulley 48 from the end 107 of the exhaust pipe 93.

The radiator 132 and the fan 134 of the heat exchanger system 130 arepositioned forwardly of the CVT 23. More specifically, as shown in FIGS.8 and 9, the radiator 132 and the fan 134 are positioned forwardly ofthe secondary pulley 48. The exhaust pipe 93 extends forward from theend 105 of the exhaust pipe 93 past the radiator 132 and the fan 134 anddownward past the radiator 132 and the fan 134 where the end 107 of theexhaust pipe 93 is connected to the muffler 96. The muffler 96 thenextends rearward under the radiator 132 and the fan 134 from the end 107of the exhaust pipe 93 and past the radiator 132 and the fan 134.

Modifications and improvements to the above-described implementations ofthe present technology may become apparent to those skilled in the art.The foregoing description is intended to be exemplary rather thanlimiting. The scope of the present technology is therefore intended tobe limited solely by the scope of the appended claims.

What is claimed is:
 1. A snowmobile comprising: a frame; a ski connectedto the frame; a seat connected to the frame for accommodating a driverof the snowmobile; a rear suspension assembly operatively connected tothe frame, the rear suspension assembly comprising: at least one sliderail; a suspension assembly drive axle defining a drive axle rotationaxis; a drive sprocket mounted to the drive axle; and a plurality ofidler wheels connected to the at least one slide rail; an endless tracksupported by the rear suspension assembly, the drive sprocket of therear suspension assembly being rotatable about the drive axle rotationaxis to drive the endless track; a motor supported by the frame, themotor comprising a shaft rotatable about a shaft rotation axis, thedrive axle rotation axis being positioned forwardly of the shaftrotation axis of the shaft of the motor, the seat being positioned abovethe motor; and a continuously variable transmission (CVT) operativelyconnecting the motor to the endless track for driving the endless track.2. The snowmobile of claim 1, wherein the CVT comprises: a primarypulley operatively connected to and driven by the motor, the primarypulley being rotatable about a primary pulley rotation axis, the primarypulley rotation axis extending parallel to the shaft rotation axis ofthe shaft of the motor, the primary pulley being operatively connectedto the shaft of the motor by one of: a chain; and a belt; a secondarypulley operatively connected to and driven by the primary pulley, thesecondary pulley being rotatable about a secondary pulley rotation axis,the secondary pulley being operatively connected to the endless track todrive the endless track; and a transmission belt connecting the primarypulley to the secondary pulley.
 3. The snowmobile of claim 2, furthercomprising: a primary pulley shaft defining the primary pulley rotationaxis, the primary pulley being mounted to the primary pulley shaft torotate therewith; and a secondary pulley shaft defining the secondarypulley rotation axis, the secondary pulley being mounted to thesecondary pulley shaft to rotate therewith, the one of the chain and thebelt being operatively connected between the primary pulley shaft andthe shaft of the motor.
 4. The snowmobile of claim 3, wherein theprimary and secondary pulley shafts are rotatably supported by theframe.
 5. The snowmobile of claim 2, wherein: the primary pulleyrotation axis extends laterally; and the primary pulley rotation axis ispositioned forwardly of the shaft rotation axis of the shaft of themotor.
 6. The snowmobile of claim 2, wherein the secondary pulleyrotation axis is positioned forwardly of the primary pulley rotationaxis.
 7. The snowmobile of claim 2, wherein: the secondary pulley isoperatively connected to the drive sprocket of the rear suspensionassembly by a link; and the primary and secondary pulleys of the CVT aredisposed laterally between the link operatively connecting the secondarypulley to the drive sprocket and the one of the chain and the beltoperatively connecting the primary pulley to the shaft of the motor. 8.The snowmobile of claim 2, wherein the drive axle rotation axis ispositioned rearwardly of the secondary pulley rotation axis.
 9. Thesnowmobile of claim 8, wherein the drive axle rotation axis ispositioned rearwardly of the primary pulley rotation axis.
 10. Thesnowmobile of claim 2, wherein the secondary pulley rotation axis isvertically lower than the primary pulley rotation axis.
 11. Thesnowmobile of claim 1, wherein the ski is a single laterally centeredski.
 12. The snowmobile of claim 3, wherein: the one of the chain andthe belt is the chain; the snowmobile further comprises: a firstsprocket mounted to the shaft of the motor; and a second sprocketmounted to the primary pulley shaft; and the chain is connected betweenthe first and second sprockets to operatively connect the shaft of themotor to the primary pulley.
 13. The snowmobile of claim 12, wherein thesecond sprocket has a smaller diameter than the primary pulley.
 14. Thesnowmobile of claim 1, wherein: the motor is an internal combustionengine; and the shaft of the motor is a crankshaft and the shaftrotation axis of the shaft of the motor is a crankshaft rotation axis.15. A snowmobile comprising: a frame; a ski connected to the frame; aseat connected to the frame for accommodating a driver of thesnowmobile; a rear suspension assembly operatively connected to theframe, the rear suspension assembly comprising: at least one slide rail;a suspension assembly drive axle defining a drive axle rotation axis; adrive sprocket mounted to the drive axle; and a plurality of idlerwheels connected to the at least one slide rail; an endless tracksupported by the rear suspension assembly, the drive sprocket of therear suspension assembly being rotatable about the drive axle rotationaxis to drive the endless track; a motor supported by the frame, themotor comprising a shaft rotatable about a shaft rotation axis, thedrive axle rotation axis being positioned forwardly of the shaftrotation axis of the shaft of the motor, the seat being positioned abovethe shaft rotation axis of the shaft of the motor; and a continuouslyvariable transmission (CVT) operatively connecting the motor to theendless track for driving the endless track.
 16. The snowmobile of claim15, wherein the CVT comprises: a primary pulley operatively connected toand driven by the motor, the primary pulley being rotatable about aprimary pulley rotation axis, the primary pulley rotation axis extendingparallel to the shaft rotation axis of the shaft of the motor, theprimary pulley being operatively connected to the shaft of the motor byone of: a chain; and a belt; a secondary pulley operatively connected toand driven by the primary pulley, the secondary pulley being rotatableabout a secondary pulley rotation axis, the secondary pulley beingoperatively connected to the endless track to drive the endless track;and a transmission belt connecting the primary pulley to the secondarypulley.
 17. A snowmobile comprising: a frame; a ski connected to theframe; a seat connected to the frame for accommodating a driver of thesnowmobile; a rear suspension assembly operatively connected to theframe, the rear suspension assembly comprising: at least one slide rail;a suspension assembly drive axle defining a drive axle rotation axis; adrive sprocket mounted to the drive axle; and a plurality of idlerwheels connected to the at least one slide rail; an endless tracksupported by the rear suspension assembly, the drive sprocket of therear suspension assembly being rotatable about the drive axle rotationaxis to drive the endless track; an internal combustion engine supportedby the frame, the engine comprising a crankshaft rotatable about acrankshaft rotation axis, the drive axle rotation axis being positionedforwardly of the crankshaft rotation axis; a continuously variabletransmission (CVT) operatively connecting the engine to the endlesstrack for driving the endless track; and a fuel tank supported by theframe and positioned rearwardly of the engine.
 18. The snowmobile ofclaim 17, wherein the fuel tank is positioned rearwardly of the seat.19. The snowmobile of claim 17, wherein the CVT comprises: a primarypulley operatively connected to and driven by the engine, the primarypulley being rotatable about a primary pulley rotation axis, the primarypulley rotation axis extending parallel to the crankshaft rotation axis,the primary pulley being operatively connected to the crankshaft by oneof: a chain; and a belt; a secondary pulley operatively connected to anddriven by the primary pulley, the secondary pulley being rotatable abouta secondary pulley rotation axis, the secondary pulley being operativelyconnected to the endless track to drive the endless track; and atransmission belt connecting the primary pulley to the secondary pulley.20. The snowmobile of claim 19, further comprising: a primary pulleyshaft defining the primary pulley rotation axis, the primary pulleybeing mounted to the primary pulley shaft to rotate therewith; and asecondary pulley shaft defining the secondary pulley rotation axis, thesecondary pulley being mounted to the secondary pulley shaft to rotatetherewith, the one of the chain and the belt being operatively connectedbetween the primary pulley shaft and the crankshaft.